6.5l N/a problem

[bchummer]

Hi guys newbie here.
I've got a '95 Hummer with a rebuilt 6.5 non turbo (about 5000 mi. on rebuild). On cold starts I'm getting alot of bluish smoke with a definite miss o one of the cylinders. After about 30-45 seconds there is a loud knocking. The smoke and the miss starts to dissapear at this point until it seems to be "warmed up" and the knocking subsides, but never really goes away.
I recently changed the injection pump and turned up my fuel which definitley made the truck run much better, but the symptoms were there before and after the pump change. I have no issues with the way the truck runs after it is warmed up, except for the knocking.
Any thoughts?
TIA

[john8662]

I'd suggest checking the injection line routing to the cylinders.

Do you have a diagram in a manual?

Perhaps one of the lines was swapped during a previous injection pump R&R.

If the lines were mis-routed previously, it stands to reason that the same thing could happen during your pump replacement as well.

I'm also moving this to the 6.5L Forum.

J

[Robyn]

Welcome to TDP

As John mentioned the routing on the lines is a good thing to check.
If this issue just came on you may have a bad injector.
Check the lines for routing to the proper cylinder and if this is ok try loosening each injector line one at a time with the r=engine running untill you find the offending hole.
Replace that injector and the issue should resolve itself,
My guess is you have a nozzle that squirting rather than spraying.

These things can and do develop an issue and start tossing out a peeeeeee stream rather than a fine mist in a cone shaped pattern.

Good luck

Robyn

[bchummer]

Thanks for the suggestions.
I wasn't sure which of the forum headings these engines should go under since they seem to have more in common with the 6.2 than the 6.5 turbo, but now i know!
I will check the routing of the lines to the pump. If this is the case would the truck still run as well as it does? I have a few of these vehicles and with this new pump, it seems to be running better than any of them. The smoke does dissapear after the truck is warmed up, would it not continue to smoke if the lines were messed up?
All the injectors were also changed recently when i first started chasing this problem. I put in turbo diesel injectors as reccomended by a local diesel shop.

Thanks,
steve